Optoelectronic devices are devices where an active material converts light energy into electricity or converts electricity into light energy. For certain optoelectronic devices the active material is highly sensitive to components found in the atmosphere.
For example, photovoltaic cells using copper indium diselenide (CIS) or copper indium gallium diselenide (CIGS) are known to be sensitive to moisture. Certain organic light emitting diodes are also known to have sensitivities to the atmosphere. Such devices are often enclosed to inhibit or prevent exposure to such atmosphere.
Multilayer optoelectronic devices typically have the active layers or portions formed directly on a transparent substrate, which is generally referred to as the front side. Many of these devices have been made using glass as the transparent substrate. Since glass has excellent barrier properties, and since many backside layers similarly have good barrier properties such as laminates comprised of metal foil, the concern has typically been about intrusion of water or oxygen at the interfaces or gaps at the sides of the packaging. To accommodate such potential leakage, it has been suggested to use getters (getters are also sometime referred to as scavengers and are substances that are added to a system to consume or inactivate traces of impurities or undesirable components) at the sides or behind the active layer. Also these devices sometimes have gaps or empty space at the sides or behind the active layer.
More recently there has been a move toward reducing the weight and increasing the flexibility of these devices. Thus, people have examined replacing glass with various transparent polymeric barrier substrates.